1. Field of the Invention
This invention relates to an evaporating heat transfer wall and particularly to an improved evaporating heat transfer wall which can advantageously transfer heat to liquid by evaporating (in a wide meaning including boiling) the liquid being in contact with the heat transfer wall.
2. Description of the Prior Art
A heat transfer wall has been proposed by Japanese Patent Publication No. 44357/1981 for advantageously transferring heat to a liquid from the surface of a plate or tube. The liquid, such as Freon, when in contact with the surface is evaporated therefrom. The heat transfer wall has a number of fine elongate tunnels adjacent to each other which are formed a minute distance under the surface of said wall. A number of fine openings in the ceilings of said tunnels for communicating the tunnels with the outside are regularly spaced by minute distances along the ceiling of each of said tunnels.
Such heat transfer wall as described above can achieve higher heat transfer performance than that of a heat transfer wall in which slit-like narrow openings are continuously defined along tunnels. However, a heat transfer wall having much higher heat transfer performance has recently been required, because of miniaturization, high-performance and the like of air conditioning apparatus or freezing apparatus etc. in which such heat transfer walls are utilized.